Dishwasher, especially domestic dishwasher

ABSTRACT

Dishwasher, in particular domestic dishwasher, comprising a crockery basket which comprises a, in particular rotating, washing arm which is supplied with water by a water transferring pipe ( 1 ), wherein the water transferring pipe ( 1 ) is connected with the crockery basket and coupling means ( 2 ) are provided for hydraulic coupling of the water transferring pipe ( 1 ) to a water supply pipe ( 3 ) which is arranged in a wall or in a corner of the washing cavity, wherein the crockery basket is adjustable in its height relatively to the washing cavity of the dishwasher and the coupling means ( 2 ) allow hydraulic coupling of the water transferring pipe ( 1 ) to the water supply pipe ( 3 ) in at least two different height positions of the crockery basket, wherein the coupling means ( 2 ) comprise a bellow that is elastically deformable, wherein the bellow ( 4 ) is connected to the water supply pipe ( 3 ) and comprises an open axial end ( 5 ) that is adapted for releasable sealing contact with the water transferring pipe ( 1 ), wherein the bellow ( 4 ) has a sealing surface ( 6 ) at its open axial end ( 5 ) which cooperates with at least one sealing surface ( 7′, 7″ ) of an adapter element ( 8 ) which is provided at the corresponding end of the water transferring pipe ( 1 ), and wherein the adapter element ( 8 ) has at least two sealing surfaces ( 7′, 7″ ) for different height positions of the crockery basket.

The invention relates to a dishwasher, preferably to a domestic dishwasher, having a crockery basket, preferably which is movable in a translational direction into a washing cavity of the dishwasher, wherein the crockery basket has a, especially rotating, washing arm which is supplied with water by a water transferring pipe, wherein the water transferring pipe is connected with the crockery basket, wherein coupling means are provided to couple the water transferring pipe to a water supply pipe which is connected with the housing of the dishwasher, wherein the coupling means allow a hydraulic coupling of the water transferring pipe to the water supply pipe.

A dishwasher of this kind is disclosed e. g. in DE 41 37 227 C2 and in DE 197 05 548 B4. A crockery basket is arranged in the dishwasher which can be pulled out of the washing cavity for loading the basket with dishes; then the basket is pushed back into the washing cavity for carrying out the washing process. The crockery basket has a rotating washing arm at its bottom side which is supplied with water by a water transferring pipe that is fixed to the bottom of the crockery basket. When the basket is shifted into its inserted position, the open end of the water transferring pipe is coupled to a water supply pipe that opens at a fixed height position in the back wall of the washing cavity.

DE 41 37 227 C2 suggests an elastic sealing element at the open end of the water transferring pipe wherein the elastic sealing element abuts against the back wall of the washing cavity and seals around the opening end of the fixed water supply pipe, that is arranged in the back wall of the washing cavity, when the basket is shifted into the washing cavity. As the sealing surface of the elastic sealing element must have a certain size to cover all possible contacts of the water transferring pipe with the opening end of the fixed water supply pipe in the back wall of the washing cavity when the basket is in different height positions, it is a drawback that the water pressure acting on the big surface of the elastic sealing element leads to significant forces which tend to push the basket against the door of the dishwasher; thus, the hydraulic forces risk to open the door unintentionally. Consequently, relatively high door closing forces are necessary to avoid the mentioned effect. That problem gets even more important with an increase in the area covered by the elastic sealing element and with the corresponding increase in water pressure that both occur when the vertical distance of the different height positions of the basket is enlarged. Therefore, the known solution is practically is limited to the use with relatively small differences in the height positions of a height-adaptable dishwasher basket.

DE 197 05 548 B4 suggests a coupling of the water transferring pipe with the water supply pipe by designing the supply pipe as a tube which is inserted into a funnel-like adapter that is formed at the corresponding end of the water transferring pipe. Sealing is obtained by employing an O-ring seal. The disadvantage of this solution is that a canting effect occurs when the basket is pulled out of the washing cavity or pushed into the same. This is basically caused by the friction of the O-ring seal inside the funnel-shaped adapter. So, water drops can easily fall down from wet wash load items when the basket is moved; consequently, cleaned dishes in a further basket that is located below can become wet again what is detrimental.

Other similar solutions are known from EP 0 872 208 A1, from WO 83/01892 A and from EP 0 796 587 A2. Some of those solutions have the drawback that a certain force must be exerted when the crockery basket is pulled out of the washing cavity to overcome the friction of the connection of the coupling means.

Consequently, a jerky movement can take place when pulling out the crockery basket. Due to this detrimental movement glasses and other dished can tilt. In addition, water that has remained on top of washload items after the end of a drying step of a wash cycle, such as on a bottom of an inverted glass, can be spilled off by such jerky movement of the basket, leading to an undesired wettening of already dried further washload items that are arranged below.

Therefore, it is an object of the invention to propose a dishwasher which overcomes the mentioned disadvantages. Consequently, a cant-free movement of the crockery basket should be ensured so that no water drops can fall down during the translational movement of the basket. Also, no high forces due to the water pressure should occur, so that no specific measures are to be taken to avoid that the door of the dishwasher opens unintentionally. Furthermore, the pulling out of the crockery basket should be of such a kind that a smooth movement takes place when exerting a force in translational direction onto the crockery basket. Also an adjustment of the height of the crockery basket should be possible over a wide range of different height positions inside the washing cavity, and with a simple and cheap design of the dishwasher.

The solution of this object according to the invention is characterized in that the bellow is connected to the water supply pipe and comprises an open axial end that is adapted for releasable sealing contact with the water transferring pipe, wherein the bellow has a sealing surface at its open axial end which cooperates with at least one sealing surface of an adapter element which is provided at the corresponding end of the water transferring pipe, wherein the adapter element has at least two sealing surfaces for different height positions of the crockery basket.

Thus, the adapter element can be readily coupled to a water supply tube that is arranged at a fixed height, i. e. at an invariably height position within the washing cavity, when the crockery basket is adjusted in its height position. A wide range of different height positions inside the washing cavity is effectively provided that avoids exerting any undue force onto the frontal door of the washing cavity in the opening direction thereof. Further, no force that could lead to any detrimental jerky movement of the crockery basket is required to overcome any friction between the coupling means and the water supply pipe when pulling the crockery basket out of the washing cavity.

Preferably, the crockery basket is adjustable in its height relatively to the washing cavity of the dishwasher, wherein the coupling means allow hydraulic coupling of the water transferring pipe to the water supply pipe in at least two different height positions of the crockery basket.

Also preferably, the adapter element comprises at least two flow paths that are arranged between the at least two sealing surfaces and the water transferring pipe. Still preferably, valve means are arranged in each flow path for closing the flow paths, in particular wherein the valve means can comprise biased flaps.

The crockery basket can be moved in a translational direction (T) into and out of a washing cavity of the dishwasher. Preferably, the washing cavity comprises A vertical back wall and two vertical side walls as well as a top wall and a bottom wall, in particular a water-collecting bottom with a sump, wherein the washing cavity is has a frontal access opening that is closed by a frontal door that is hinged around an axis that is located about the lower edge of the door. Still preferably, the crockery basket can moved in an essentially horizontal plane through into and out of a washing cavity through the frontal access opening thereof. The height-adjustable crockery basket can be moved in at least two different horizontal planes with respect to the vertical axis of the washing cavity.

The bellow is made of a suitable elastic material and has preferably an essentially cylindrical shape for hydraulically coupling of the water supply pipe to the water transferring pipe and that is stowable in its axial direction, wherein the axis of the bellow is directed in the translational direction of the crockery basket.

The at least one sealing surface of the adapter element is preferably flat. The adapter element preferably has an elongated shape at its axial end directed to the bellows, preferably a vertically elongated shape, and narrows to its axial end where the water transferring pipe is arranged.

Furthermore, a centering device can be arranged within the bellow, that is adapted for centering the water supply pipe relatively to the water transferring pipe in at least two different height positions of the crockery basket. The centering device is connected to the water supply pipe directly or indirectly, wherein the adapter element has at least two cooperating resting surfaces for the centering device that are arranged in corresponding height positions. In that case the support element has preferably a conical shape in its axial end region. The adapter element preferably has two cooperating resting surfaces for the centering device.

The water supply pipe and the adapter element can have cooperating force-uptaking means. The force-uptaking means can comprise a pin extending in the translational direction of the crockery basket that is connected to the adapter element or to the water supply pipe and a corresponding holding element that comprises at least one, preferably at least two, reception bores for receiving said pin that is connected respectively to the water supply pipe or to the adapter element. The reception bores are preferably arranged at height positions that correspond to height positions of the height-adjustable crockery basket and thus allow stabilization of the interaction of the centering device with the cooperating resting surfaces of the adaptor element.

Preferably the valve means are arranged adjacent to the sealing surfaces. A valve means comprises a flap, preferably a flap biased versus its closed position. The flap can be biased by a spring element. Preferably, the valve means is opened by the centering device when the crockery basket is fully inserted into the washing cavity.

Thus, the invention allows to pull out the crockery basket without any cant-effect. Also, the operation is easy for the user of the dishwasher. And it is ensured that remaining water drops on the basket do not fall down.

The pins and the corresponding holding element support the basket when it is fully loaded; so, not the complete weight must be carried by the centering device.

Due to the small size of the essentially cylindrical bellow that needs to have only a sufficient size to seal a single flow path of the adapter element, the hydraulic forces acting on the water transferring pipe and on the basket remain small. Consequently, no specific measures must be taken to avoid an unintentional opening of the door of the dishwasher. The door latch does not have to carry big forces.

Due to the use of a single and quite small bellow for all height positions of the crockery basket the forces stay small. Also a simple and cheap design becomes possible. This beneficial effect is particularly obtained by the arrangement of the bellow at the rear side of the washing cavity in a combination with (at least) two corresponding flap valves which are arranged inside the adapter in the respective desired height positions of the crockery basket. The sealing is established by the bellow. The free flap valve(s) ensures merely that no liquid leaves the opening which is not sealed by the bellow.

In the drawings an embodiment of the invention is depicted.

FIG. 1 shows a perspective view of coupling means for coupling of a water transferring pipe with a water supply pipe, wherein two parts of the coupling means are not yet in contact,

FIG. 2 shows a sectional view through the coupling means according to FIG. 1,

FIG. 3 shows a side view of the coupling means being in contact, wherein a crockery basket (not shown) is in a lower position,

FIG. 4 shows a sectional view through the coupling means according to FIG. 3,

FIG. 5 shows a side view of the coupling means being in contact, wherein a crockery basket (not shown) is in an upper position,

FIG. 6 shows a sectional view through the coupling means according to FIG. 5.

In FIG. 1 and FIG. 2 coupling means 2 are shown which can hydraulically couple a water supply pipe 3 with a water transferring pipe 1 (shown with dotted lines in FIG. 1). The pipes 1, 3 and the coupling means 2 are part of a domestic dishwasher. The ascending water supply pipe 3 is preferably firmly connected with a housing (not shown) of the dishwasher. The water supply tube 3 can be arranged in a back wall of the washing cavity (not shown) of the dishwasher. The supply tube can be arranged behind the back wall or can be an integral part of it. Its opening can be arranged at a fixed, i. e. an invariable, height position within the back wall of the washing cavity. The supply tube opens into the washing cavity. The water transferring pipe 1 is connected to a crockery basket (not shown) and supplies a rotating washing arm (not shown) with water which is arranged at the bottom side of the crockery basket.

The crockery basket can be pulled out of the washing cavity of the dishwasher and can be pushed into the same, i. e. it is movable in a translational direction T relative to the housing of the dishwasher and the washing cavity respectively.

Preferably, the translational direction T is essentially horizontal and the washing cavity is closable by a front door (not shown).

To ensure a cant-free coupling and de-coupling of the pipes 1, 3 and to avoid that water drops fall down from the movable upper crockery basket on washed dishes in a lower crockery basket and make them wet during the coupling and de-coupling process of the pipes 1, 3 the following design is proposed:

The ascending water supply pipe 3 bears a bellow 4 which has an essentially cylindrical shape. The axis of the bellow 4 is directed into the translational direction T. At its open axial end 5 the bellow 4 has a sealing surface 6. For interaction with the bellow 4 an adapter 8 is mounted at the corresponding axial end of the water transferring pipe 1. The adapter 8 has a face side directed to the bellow 4, where two sealing surfaces 7′ and 7″ (for two different heights of the basket) are arranged. The sealing surface 6 of the bellow 4 and the sealing surfaces 7′ or respectively 7″ of the adapter 8 cooperate to establish a hydraulic coupling between the pipes 1, 3.

Therefore, the bellow 4 is elastic (stowable) in the translational direction. It consists of rubber material or the like.

A mechanical guidance and also some support is established by a centering device 9 which is preferably firmly connected with the water supply pipe 3, as can best be seen in FIG. 2. The centering device 9 also bears the bellow 4 in the depicted embodiment of the invention. The centering device 9 has a conical shape in its axial end which is directed to the adapter element 8. Correspondingly, the adapter element 8 is equipped with resting surfaces 10′ and 10″ to establish a guiding and resting area for the centering device 9.

If the water transferring pipe 3 together with the adapter element 8 is moved in the translational direction T and the bellow 4 contacts the adapter element 8—see FIG. 3 till FIG. 6—the centering device 9 is resting at one of the resting surfaces 10′ or respectively 10″, depending of the height position at which the crockery basket is arranged.

Furthermore, force-uptaking means 11, 12 are arranged at the coupling means 2 to ensure a defined relative position between the two pipes. The force-uptaking means 11, 12 comprise a pin 11 which is arranged at the adapter element 8. The water supply pipe 3 is equipped with a holding element 12. The holding element 12 has two reception bores 12′ and 12″ for two different heights of the crockery basket. As can be seen in FIG. 4 for a lower position and in FIG. 6 for an upper position of the basket the pin 11 is engaged in a respective reception bore 12′ or 12″.

The force-uptaking means ensure that the bellow 4 hits exactly to the respective sealing surface 7′ or 7″ of the adapter element 8 and takes all forces which could be caused by the loading of the basket and thus in a undefined height position.

The adapter element 8 comprises at least two flow paths 12′ and 13′ (see FIG. 2) in order to allow to couple the adapter element 8 to the water supply pipe 3 in at least two different heights. To ensure a defined water flow through the adapter element 8 and through the respective flow path valve elements 14 are arranged in the adapter element 8. The valve elements 14 are flaps which are biased by a spring element (not shown). As can be seen in FIG. 4 and in FIG. 6 the centering device 9 with its conical-shaped end opens the flap 14 when the crockery basket is pushed into its fully inserted position inside the washing cavity of the dishwasher. So, the flow of the water is clearly defined by the respective opened flap 14.

By the dishwasher of the invention it becomes easily possible to supply water from the base of the dishwasher to the (upper) crockery basket without neither canting of the basket when pulling out the basket of the washing cavity nor applying an undue pressure to the front door by a large bellow, wherein different height positions of the basket are possible.

REFERENCE NUMERALS

1 Water transferring pipe

2 Coupling means

3 Water supply pipe (ascending pipe)

4 Bellow

5 Open axial end

6 Sealing surface

7′ Sealing surface

7″ Sealing surface

8 Adapter element

9 Centering device

10′ Resting surface

10″ Resting surface

11, 12 Force-uptaking means

11 Pin

12 Holding element

12′ Reception bore

12″ Reception bore

13′ Flow path

13″ Flow path

14 Valve means (flap)

T Translational direction (horizontal) 

1. Dishwasher, in particular domestic dishwasher, comprising a crockery basket which comprises a rotating washing arm which is supplied with water by a water transferring pipe, wherein the water transferring pipe is connected with the crockery basket and coupling means are provided for hydraulic coupling of the water transferring pipe to a water supply pipe which is connected with the housing of the dishwasher, wherein the crockery basket is adjustable in its height relatively to the washing cavity of the dishwasher and the coupling means allow hydraulic coupling of the water transferring pipe to the water supply pipe in at least two different height positions of the crockery basket, wherein the coupling means comprise a bellow that is elastically deformable, wherein the bellow is connected to the water supply pipe and comprises an open axial end that is adapted for releasable sealing contact with the water transferring pipe, wherein the bellow has a sealing surface at its open axial end which cooperates with at least one sealing surface of an adapter element which is provided at the corresponding end of the water transferring pipe, wherein the adapter element has at least two sealing surfaces for different height positions of the crockery basket.
 2. Dishwasher according to claim 1, wherein the adapter element comprises at least two flow paths that are arranged between the at least two sealing surfaces and the water transferring pipe.
 3. Dishwasher according to claim 2, wherein valve means are arranged in each flow path for closing the flow paths, and wherein the valve means are arranged adjacent to the sealing surfaces.
 4. Dishwasher according to claim 3, wherein the valve means comprise biased flaps, and wherein the flaps are biased by a spring element.
 5. Dishwasher according to claim 1, wherein the crockery basket is movable in a translational direction into and out of a washing cavity of the dishwasher.
 6. Dishwasher according to claim 5, wherein the bellow is elastically deformable in the translational direction of the crockery basket.
 7. Dishwasher according to claim 1, wherein the water supply pipe is arranged in a back wall of the washing cavity.
 8. Dishwasher according to claim 1, wherein the bellow has an essentially cylindrical shape, and wherein the axis of the bellow is directed in the translational direction of the crockery basket.
 9. Dishwasher according to claim 1, wherein the at least one sealing surface of the adapter element is flat.
 10. Dishwasher according to claim 1, wherein the adapter element has an elongated shape at its axial end directed to the bellow, wherein the adapter element is a vertically elongated shape, and wherein the adapter element narrows to its axial end where the water transferring pipe is arranged.
 11. Dishwasher according to claim 1, wherein a centering device is arranged within the bellow that is adapted for centering the water supply pipe relatively to the water transferring pipe in at least two different height positions of the crockery basket, wherein the centering device is connected to the water supply pipe directly or indirectly, and wherein the adapter element has at least two cooperating resting surfaces for the centering device that are arranged in corresponding height positions.
 12. Dishwasher according to claim 11, wherein the centering device has a conical shape in its axial end region.
 13. Dishwasher according to claim 16, wherein the valve means are opened by the centering device when the crockery basket is fully inserted into the washing cavity.
 14. Dishwasher according to claim 1, wherein the water supply pipe and the adapter element comprise cooperating force-uptaking means for taking up forces in the vertical direction that are caused by the weight of a load of the crockery basket.
 15. Dishwasher according to claim 14, wherein the force-uptaking means comprise a pin extending in the translational direction of the crockery basket that is connected to the adapter element or to the water supply pipe and a corresponding holding element that comprises at least one reception bores for receiving said pin that is connected respectively to the water supply pipe or to the adapter element.
 16. Dishwasher according to claim 3, wherein a centering device is arranged within the bellow that is adapted for centering the water supply pipe relatively to the water transferring pipe in at least two different height positions of the crockery basket, wherein the centering device is connected to the water supply pipe directly or indirectly, and wherein the adapter element has at least two cooperating resting surfaces for the centering device that are arranged in corresponding height positions. 